Miller bobcat 225g plus welding problem

The toroid transformer (looks like a donut) has wires, and connectors which feed a small voltage to the idle module. Since works with grinder, I'd look for corroded connections including rusty grounds. It takes one volt ac to idle mod to trigger.

it will stay running

put 12 volts to the coil and see if it pulls in. Could be coil, idle module, ignition switch, or wiring. Get a 12v test light and trace it.

First off, check all of your welding cables to make sure they're in good shape, then check for tight cable connections. Is your machine staying at low idle speed while trying to weld? If so, Switch the idle select into the 'weld' position and make sure the high RPM's initiate. Try welding again. Better? Could be a number of things, if not.

If your Miller Bobcat 250 runs great, the generator works, but the welder will not weld, even though the fuses are good, it could be caused by a few different things. Here are a few things you can try to fix the issue:

1. Check the welding settings, make sure they are appropriate for the type of welding you are doing. Make sure the voltage and amperage are set correctly.
2. Check the ground connection, make sure it's clean and tight. The ground connection must be secure for stable welding.
3. Inspect the welding cables and make sure they are in good condition and that the connections are tight.
4. Check the welding gun and make sure it's clean and in good condition.
5. Check the main contactor and make sure it's engaging and disconnecting properly.
6. Check the main circuit breaker and make sure it's not tripped.
7. Check the power output of the generator and make sure it's within the correct range.
8. Check the control circuit and make sure that it's not damaged or malfunctioning.

It's important to check the manual of the welder for troubleshoot steps and also check the warranty of the welder and see if it's still covered by the manufacturer. If you are not able to find the problem or if you are not familiar with welding equipment, it's best to take your welder to a qualified Miller Electric welder repair service center, they will be able to diagnose and fix the issue.

better take help from service bobcat, u cannot fix

A welder does not speed up when an arc is struck. It is normal for a gas welder to stay at a high rpm. If it did not, it would be very hard on the machine as a high amperage is needed to start an arc for welding, and to be consistant. Unlike a generator which will "idle down" when not in use.

Simple first, make sure you have it set to auto idle

Take off shroud, look at where the positive lead hooks into the transformer. You may find that the wire has melted, If you are lucky, you can loop it tnough to make a fresh connection. (also check the negitive)

You can get this manual from the following link http://personafile.com/Miller-Welding-Equipment-BOBCAT-225G-P9207349821373.htm

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